This invention relates to methods for preparing and preserving fresh, ripe, edible melon pieces so that the pieces may be stored for long periods of time without appreciable loss of natural flavor, color and texture. More particularly, the method pertains to the cutting and/or segmenting of fresh edible melon tissue into pieces, packing the melon pieces in a container, sealing the container, cooling the melon pieces, and storing the container at refrigerated temperatures.
It is well-known that the quality of whole or cut fresh melons deteriorates rapidly at ambient temperatures. The deterioration rate can be slowed by maintaining the melons at refrigerated storage temperatures. Still, in most cases, the shelf-life of fresh, ripe refrigerated melon pieces is only a few days.
In addition to a temperature factor, the composition of gases in the storage atmosphere enveloping the melon can influence and prolong the storage life of whole fresh melons. There is evidence that higher carbon dioxide levels and lower oxygen levels advantageously lower the respiration and ripening rates of melons. On the negative side, however, undesirable physiological disorders and deterioration in quality of the melon may occur. In particular, strong off-flavor in the melons may develop.
Modified atmosphere packaging is the term commonly used for the storage of food in a flexible or semi-flexible bag or pouch with an internal atmosphere which is not controlled but may indeed vary in composition during storage of the commodity due to gas transmission through the walls of the bag or pouch. Plastic films have been used to cover whole melons in containers so that the atmosphere enveloping the melon can be modified. Polyethylene box liners, either sealed or unsealed, have been employed commercially for some time for the storage and transportation of apples and pears. It has been found that the respiration of the whole melon in a sealed, air containing, polyethylene bag will cause a rise in carbon dioxide level and a corresponding reduction in oxygen content in the bag interior. High levels of carbon dioxide (5% or higher) have been found to be harmful because they can cause unsightly melon discoloration and "off-flavor" development due to carbon dioxide toxicity. To reduce the risk of carbon dioxide toxicity, the bags are either unsealed or perforated to permit atmosphere exchange, or packets of fresh hydrated lime, which reacts with the carbon dioxide to reduce its level, are placed in the bag prior to sealing.
The inability to store fresh ripe melons for longer periods means that a considerable amount of fresh melon is lost due to spoilage. Thus, the development or discovery of a method to capture and retain the high quality attributes of ripe melons for prolonged storage periods would be extremely advantageous.